Got both done Monday. It drives very close to before initial AEM. A little hesitation when cold. Buying fuel at the same place for for 2.03/2.05 and making two, 250 mile round trips a week and showing a 24.5 mpg. The way I drive. Here's the question, When I installed the factory ECU, couple days before service. The DEF showed more than a 1/4 tank increase. it went from just below a 1/4 to over a half. Today to do a sanity check I put in a full 2 1/2 gal and its now reading full. Had an oil change done and reset it before taking in. Not going to swap back until I do a couple round trips to see the mileage difference. The coolant tank looks darker and there is a new little sticker.